Estimate the cost to install a radon mitigation system. Pick foundation type, system type, fan size. 2026 data; not a contractor bid.
| Item | Quantity | Estimated range |
|---|
Got a contractor quote? Compare it to the planning range.
Your foundation determines the system, which sets the price. All figures are installed, including the fan, electrical, and a post-mitigation test:
| System | Foundation | Installed cost |
|---|---|---|
| Sub-slab depressurization (SSD) | Basement | $1,200 – $2,200 |
| SSD | Slab-on-grade | $1,500 – $2,800 |
| Sub-membrane | Crawl space | $1,800 – $3,200 |
| Block-wall depressurization | Block foundation | $2,200 – $3,800 |
The standard fix is simpler than it sounds: a pipe is sealed through the slab and a continuous fan ($220–$470 depending on the flow needed) creates gentle suction in the gravel under your foundation. That pulls radon gas out from beneath the slab and vents it above the roofline, where it disperses harmlessly before it can enter the living space. Large or segmented slabs may need additional suction points ($280–$450 each). Routing the pipe through an interior closet ($350–$600) hides it for curb appeal; an exterior run is cheaper but visible.
A radon system isn't finished until it's proven to work. Retest after installation ($100–$200) to confirm levels dropped below the EPA action level of 4 pCi/L — a well-designed system typically brings most homes well under that. Use an installer certified by the NRPP or NRSB; radon is a recognized lung-cancer risk, so this isn't a job for guesswork. One ongoing note: the fan is the only moving part and lasts roughly 5–10 years; replacing it ($220–$470) is the system's main long-term maintenance.
A standard sub-slab depressurization (SSD) for a basement runs $1,200-$2,200 installed including fan, electrical, and post-test. Slab-on-grade $1,500-$2,800. Crawl space sub-membrane $1,800-$3,200. Block-wall systems $2,200-$3,800.
Most jurisdictions require a permit ($75-$200) and many require the contractor be NRPP / NRSB certified. Always test before and after.
A properly designed SSD reduces radon by 50-99% in most homes. Post-test should show under 4 pCi/L (EPA action level). If not, additional suction points or a higher-flow fan may be needed.
Most systems use sub-slab depressurization: a pipe and a continuous fan create suction under the foundation slab and vent radon gas above the roofline before it enters the home. The fan runs continuously and is the only moving part.
Below the EPA action level of 4 pCi/L, and a well-designed system usually brings homes well under it. Always confirm with a post-mitigation test ($100-$200) - a system that is installed but not verified is not finished.
Radon fans run continuously and typically last about 5-10 years. Replacement is $220-$470 depending on the model and is the system\u2019s main long-term maintenance item; the piping itself lasts for decades.
Most jurisdictions require a permit; a few exempt very small jobs. Always confirm with your local building department.
Depends on scope; basic jobs are 1-3 days, complex jobs run 1-2 weeks.
Get 2-3 written quotes for the same scope. Big spreads usually mean different inclusions, not necessarily different value.
Workmanship warranty 1-5 years from the contractor; manufacturer warranty on materials separately.
Some scopes are DIY-friendly with rented tools; others (gas, electrical, structural, plumbing) require licensed trades by code.
